Liquid crystal display devices, having advantages in the thin profile, light weight, and low power consumption, are widely used as display devices such as televisions, personal computers, and PDAs. Particularly in recent years, liquid crystal display devices have been rapidly increased in size as seen in liquid crystal display devices for televisions.
Pretilt angle imparting technology using a polymer (hereinafter, also referred to as a PSA (Polymer Sustained Alignment: alignment maintaining) layer) to achieve high luminance and high-speed response has been drawing attention recently (see, for example, Patent Literatures 1, 2). In the PSA technology, a liquid crystal composition prepared by mixing liquid crystals with polymerizable components such as monomers and oligomers is sealed between substrates. Then, the polymerizable components are polymerized into a polymer while a voltage is applied between the substrates to tilt liquid crystal molecules. Thereby, the liquid crystals have the prescribed pretilt angles even after elimination of applied voltage, and thus the alignment direction of the liquid crystals may be defined. The polymerizable components are polymerized by irradiation with heat or light (ultraviolet rays). The PSA technology may achieve high-speed response without reducing an aperture ratio.